BERLIN (Reuters) - German prosecutors have charged a 24-year-old man with helping a radical Islamist group whose followers have confessed to planning attacks on U.S. targets in Germany.

The federal prosecutor's office said it had charged the man it identified as Kadir T. with supporting the Islamic Jihad Union (IJU), an organization often linked to a militant Islamist movement that originated in Uzbekistan.

Four men affiliated to the IJU and known as the "Sauerland group" are on trial in the western city of Duesseldorf for planning bomb attacks on U.S. institutions in Germany.

The group has confessed to planning attacks, and some of its helpers have already been jailed, though a verdict on the four is very unlikely before mid-2010, the Duesseldorf court said.

Prosecutors said Kadir T., who holds both German and Turkish citizenship, had attended regular meetings led by a member of the group, and had bought equipment for the IJU which ended up in Waziristan, on Pakistan's border with Afghanistan.